select productid from orders where count(productid)>1
select productid from orders where max(productid)>1
select productid from orders where having count(productid)>1 group by productid
select productid from orders group by productid having count(productid)>1
难度:2
答案:D
知识点:SQL
解析:命令顺序为:select, from, where, group by, having, order by, limit